Fuel admission device for internal combustion engines



Nov. 10, 1942. r J BARTON FUEL ADMISSION DEVICE FOR INTERNAL COMBUSTIONENGINES .Filed April 24, 1939 /V////// r J m. y i

. vN NN mm on FM Patented Nov. 10, 1942 FUEL ADMISSION DEVICE FORINTERNAL COIWBUSTION ENGINES Jim Barton, Pioneer, Tex., assignor toPhillips Petroleum Company, a corporation of Delaware Application April24, 1939, Serial No. 269,777 3 Claims. (01. 129-92) This inventionrelates to internal combustion engines and in its more specific aspectsto fluid fuel admission devices for internal combustion engines.

Heretofore, it has generally been the practice in the operation oftwo-cycle engines to introduce the fuel under pressure to the head endof the cylinder, during the compression stroke of the piston, by meansof a fuel injector valve which includes a valve, a valve stem and aspring.

virtue of the simplicity of my design and the relatively few parts whichare subject to wear, the maintenance and replacement costs are reducedto a minimum.

A still further object of my invention is to provide a fuel admissiondevice which is adapted to The valve is opened through its cooperationwith a rocker arm and a push rod or valve shaft, the latter beingactuated by a geared connection at the crank end of the engine. Afterthe fuel has been admitted to the cylinder, the above mentioned springtends to close the valve. The timing (opening and closing) of the valveis controlled by a cam which operates one end of the rocker arm atpredetermined intervals to open and close thevalve.

The present invention contemplates the admission of fuel into the headend of an internal combusion engine cylinder by means of a device whichconsists of a Valve, astem and a spring all acting with a flexiblediaphragm. The valve is operated by the alternate pressure and vacuumcreated behind the piston during the expansion and compression strokesof the piston instead of by means of the complicated mechanism employedin the past. A small bore conduit places the main body of my device incommunication with the back end of the cylinder, so that, as the pistonmoves forward on the compression stroke, a

vacuum is created behind the piston. During the compression stroke, aspring closes the valve and cuts off the fuel supply. When the pistonmoves toward the back end of the cylinder on the expansion stroke of thepiston, a pressure is produced in the conduit which actuates thediaphragm to open the valve and allows fuel to be injected into thecylinder. This device eliminates the former rocker arm, push rod and camarrangement and effects a number of advantages which will be readilyunderstood by those skilled in the art on a perusal of the detaileddescription hereinafter presented.

The primary object of this invention is to provide a fuel admissiondevice which is adaptable to increase the power delivered by internalcombustion engines.

Another object of my invention is to provide a fuel admission devicewhich is operable in a positive and dependable manner on alternatepressures and vacua created behind the piston in internal combustionengines during expansion and compression strokes.

A further object of this invention is to provide an internal combustionengine fuel admission device which is simple in design, rugged inconstruction and inexpensive to manufacture. By

be readily substituted for other types of fuel admission means. Thisconversion may be quick ly and inexpensively accomplished at the placeof use, thereby avoiding costly delays which would result if the entireengine had to be returned to the factory or shipped to a shop which isespecially equipped to carry out this work.

These as well as additional objects and advantages will be apparent byreference to the following specification and annexed drawing which is alongitudinal cross section view through the center of an internalcombustion engine cylinder illustrating a preferred embodiment of myinvention installed thereon.

Referring to the drawing, I have denoted therein an internal combustionengine cylin'der l, which is provided with the usual water-jacket 2 andis rigidly supported on an engine frame 3 by means of bolts 4. A piston5 reciprocates Within the cylinder and is connected to a piston rod 6which passes through a packing gland 1 in the back end of the cylinder.A conventional spark plug 8 and air starting valve 9 are indicated atthe head end of the cylinder. Air for normally operating the engine isintroduced from the outside into an air inlet passageway I0, passesthrough air inlet valves H and chamber l2, and thence. is admitted intothe cylinder by way of inlet ports l3 and 14. The products of combustionare emitted from the cylinder by way of 'exhaust ports [5 and an exhaustoutlet 16.

A housi g, generally indicated by reference numeral I1, consists of abase member l8 constituting a fuel compartment, a top member 19, and twointermediate members 20 and 2|, all assembled by any suitable meansknown in the art into a single compact unit. The portion of the housingabove base member l8 may be properly termed a control compartment. Thehousing is securely mounted in the head end of the cylinder so that anopening 22, which serves as a seat for valve 23, is substantially flushwith the inner surface of the cylinder. The base member is provided witha. fuel inlet opening 24 for supplying fuel from a source not shown.Attached to valve 23 is an extensible stem which is composedof a pair ofrods 25 and, 26 and a connector 21 which is in threaded engagement withan end of each rod, as illustrated, in order to allow for ready end ofthe valve stem, or rod 26, is slidably supported in a sleeve 29 which isthreadedly mounted in a partition 30 in the housing. Concentric with rod26 are a collar 3| and a compression spring 32. A bearing member 33,which is in threaded engagement with the upper extremity of rod 26, isprovided with a shoulder 34 to receive and retain the compression springin position. It will be observed that sleeve 29, collar 3|, spring 32,and member 33 all coact with the valve stem to normally maintain valve23 in closed position. The force exerted by the compression spring uponthe valve stem may be readily varied by adjusting connector 21, sleeve29, member 33, or any combination of these elements. In this manner Ihave provided a wide range of adjustability in the means for urging thevalve into closed position. A convex surface or face 35 on member 33bears against a flexible diaphragm 35 which is firmly held between topmember l9 and intermediate member 20 of the housing assembly.

A suitable conduit arrangement establishes communication between theinterior of the housing to the left of the diaphragm and chamber l2 inthe engine cylinder. The conduit arrangement illustrated in the drawingconsists of a series of tubing sections 31 which are joined into acontinuous line of tubing by elbows 38, a coupling 39 and a pressurecontrol valve iii.

For the purpose of outlining the mode of operation of my instantinvention, it is first assumed that the piston 5 is moving in thedirection indicated by the arrow on piston rod 5, that is, to the leftor toward the head end of the cylinder. It will be noted that air portsi3 and exhaust ports l5 are all covered by the piston during this, thecompression stroke of the piston. Starting valve 9 and fuel admissionvalve 23 are both closed, as indicated in the drawing; and the fuel andair mixture, which has been previously admitted to the cylinder, iscompressed preparatory to firing. During this step in the operation, apartial vacuum is created back of the piston, extending from the backend of the cylinder, through air port it, air chamber l2, the conduitarrangement, and lastly to the upper end of housing ll. The effect ofthis partial vacuum is to draw diaphragm 36 toward the housing topmember i9 and permit compression spring 32 to urge valve 23 intocompletely closed position.

As the piston moves in the opposite direction during its expansionstroke, it will uncover exhaust ports l5 before air ports l3, allowingthe products of combustion to exhaust by way of outlet |6. Air admittedthrough inlet If) and valves H into chamber I2, is introduced to thehead and back ends of the cylinder by ports I 3' and M, respectively.Continued travel of the piston in its expansion stroke compresses theair admitted into the back end of the cylinder and transmits this airunder pressure through port M. chamber I2, the conduit arrangement, andthence against the diaphragm in the housing. The diaphragm is forcedagainst face 35 of member 33, actuating the valve stem in counteractionwith the compression spring, thus opening valve 23 to admit fuel fromfuel inlet 24 into the head end of the cylinder. When the piston hascompleted its expansion stroke and starts on its next compressionstroke, the pressure exerted by the air on the diaphragm will berelieved; and, due to the action of compression spring 32, valve 23 willbe returned to closed position.

It is merely a matter of mechanical skill to properly design and balancethe diaphragm with relation to the spring means in order to provide amechanism possessing the desired degree of sensitivity. Furthermore, bythe use of control valve 40, the pressure effect of the air which iscompressed in the back end of the engine cylinder may be regulated toincrease or decrease the time period required to actuate the diaphragmand open the admission valve against the action of the compressionspring. This valve is utilized both in starting and operating the engineunder various load conditions.

From the foregoing it is believed that the construction, operation andadvantages of my present invention will be readily comprehended bypersons skilled in the art. It is to be clearly understood, however,that the form of my invention herewith shown and described is to betaken as a preferred example of the same and that various changes in.the size, shape, and arrangement of parts may be resorted to withoutdeparting from the spirit of my invention as defined by the appendedclaims.

I claim:

1. In apparatus for admitting fuel into an internal combustion enginehaving a cylinder and a piston arranged to reciprocate therein, thecombination comprising a body member connected to the cylinder andincluding a control compartment and a fuel compartment, means forsupplying fuel to the fuel compartment, a valve associated with the fuelcompartment for controlling the flow of fuel into the cylinder, meansfor creating fluid pressure on each expansion stroke of the piston, andmechanical means in the control compartment responsive to the fluidpressure created on each expansion stroke of the piston, said lastmentioned means including a diaphragm for positively actuating thevalve. to open the same and admit fuel intothe cylinder.

2. In apparatus for admitting fuel into an internal combustion enginehaving a cylinder and a piston arranged to reciprocate therein, thecombination comprising a body member connected to the cylinder andincluding a control compartment and a fuel compartment, means forsupplying fuel tothe fuel compartment, a valve associated with the fuelcompartment for controlling the flow of fuelinto the cylinder, means fornormally maintaining said valve in closed position, means for creatingfluid pressure on each expansion stroke of the piston, and mechanicalmeans in the control compartment responsive to the fluid pressurecreated on each expansion stroke of the piston, said last mentionedmeans including a diaphragm for positively actuating the valveto openthe same and admit fuel into the cylinder.

3. In a fluid operated fuel admission device for an internal combustionengine having a cylinder and a piston arranged to reciprocate therein,the combination comprising a body member adapted to be connected to thehead end of the cylinder and including a fuel compartment and a controlcompartment, a fuel inlet and a fuel outlet for the fuel compartment, avalve associated with the fuel outlet for controlling the admission offuel into the cylinder, means for normally maintaining the valve inclosed position, and a diaphragm in the control compartment, saiddiaphragm be-- ing responsive to fluid pressure created on each strokeof the piston to open the valve and admit fuel into the cylinder.

' JIM BARTON.

